WO2007043617A1

WO2007043617A1 - I/o request processing system and method

Info

Publication number: WO2007043617A1
Application number: PCT/JP2006/320399
Authority: WO
Inventors: Masao Shimada
Original assignee: Nec Corporation
Priority date: 2005-10-12
Filing date: 2006-10-12
Publication date: 2007-04-19
Also published as: US7707332B2; US20090049217A1; JP2007108950A

Abstract

There is provided an I/O request processing system capable of reducing the maximum value of the time required until an I/O request of each external device is registered. An I/O request reception unit (501) receives an I/O request issued by an external device (600). A process information holding unit (510) holds an I/O request delay time (512) for each external device (600). A priority process judgment unit (520) registers an I/O request having a maximum I/O request delay time (512) among the I/O requests which have been received in an I/O request queue (540).

Description

Specification

iZo request processing system and method

Technical field

[0001] The present invention relates to an iZo request processing system and method, and more particularly, to an iZo request for an input / output device (data input / output device), and for data received between the external device and the input / output device. The present invention relates to an iZo request processing system that controls input / output, and an iZo request processing method in such an iZo request processing system.

Background art

[0002] An iZo request processing system receives an iZo request issued by an external device such as a process, and based on the received iZo request, the external device force outputs data to the input / output device, and the input / output device force also reads the read data. Deliver to an external device. An iZo request processing system usually has an iZo request queue, sequentially registers iZo requests issued to the same I / O device in the queue, reads the registered iZo requests one by one, Execute iZo processing.

[0003] As a conventional technique in a system for processing a bag request, there is a technique described in Japanese Patent Laid-Open No. 63-180338. In this technology, tasks are managed with activation priority, the task with the highest activation priority is activated, and the activated task preferentially uses iZo resources. As a technology for dispatch control of tasks including iZo requests,

There is a technique described in Japanese Patent No. 63-39041. With this technology, process dispatch priority is controlled using the CPU consumption time of the process and the IZO processing time of the process as parameters. For example, for processes with a large amount of IZO processing, set a high dispatch priority so that iZo resources are used preferentially.

[0004] However, in each of the above prior arts, which task has a high degree of urgency due to a plurality of tasks required for the same resource (input / output device) is considered. No! For this reason, tasks that have a long delay time for iZo requests and tasks that continue to fail iZo requests cannot be used. As a result, the slew rate decreases and the delay time increases, and the upper system of the iZo request issuer In the process, there is a problem that it is necessary to provide a large number of buffers in order to prevent the occurrence of buffer overflow and underflow.

Disclosure of the invention

[0005] The present invention solves the above-mentioned problems of the prior art, secures the slew rate, minimizes the maximum delay time of iZo request of each external device, and sets the buffer of the host system or application. By preventing overflow and underflow, the objective is to provide an ιΖο request processing system that does not require a large amount of nother.

[0006] In the first aspect, the present invention registers the ΙΖΟ request that has also received the external device power in the ΙΖΟ request queue, and establishes a connection between the external device and the input / output device based on the iZo request registered in the iZo request queue. IZo request processing system that controls the input and output of data performed between the iZo request receiving unit that receives the iZo request issued by the external device, and the process from receiving the iZo request to registering it in the iZo request queue Referring to the external device information holding unit that stores the delay time, among the iZo requests received by the iZo request reception unit, the priority external device determination unit that registers the iZo request with the longest delay time in the iZo request queue An iZo request processing system is provided.

[0007] In the second aspect, the present invention registers the ΙΖΟ request that has also received the external device power in the ΙΖΟ request queue, and establishes a connection between the external device and the input / output device based on the iZo request registered in the iZo request queue. IZo request processing system that controls input / output of data performed between the iZo request processing system, the iZo request processing system accepting an iZo request issued by the external device, and the iZo request The processing system refers to the external device information holding unit that stores the delay time from when the iZo request is accepted until it is registered in the iZo request queue. Among the accepted iZo requests, the IΖo request with the longest delay time is stored. And a step of registering the request in the iZo request queue.

[0008] In the bag request processing system and method according to the first and second aspects of the present invention, the received I

Iο Preferentially register the iZo request issued by the external device with the longest delay time, that is, the longest time from the iZo request reception time to the current time in the iZo request queue. By doing this, the maximum delay time of iZo request of each external device is set. It can be minimized to prevent buffer overflow and underflow in higher-level systems and applications.

[0009] In the third aspect, the present invention registers an IZO request that has also received external device power in an IZO request queue, and establishes a connection between the external device and the input / output device based on the ιΖο request registered in the ιΖο request queue. ΙΖο request processing system that controls the input and output of data performed between the ι ο request accepting unit issued by the external device, and when the ιΖο request accepting unit accepts an iZo request, IZo requests issued by the device are not continuously registered in the iZo request queue.The external device information holding unit stores the continuous registration failure time for each external device that issued the iZo request, and the specified value for the continuous registration failure time. A priority external device determination unit that determines whether or not to register the received iZo request in the iZo request queue with reference to the stored continuous registration failure time prescribed value storage unit is provided. IZo request processing system is provided.

[0010] In the fourth aspect, the present invention registers an iZo request that has also received an external device capability in an iZo request queue, and sets the iZo request between the external device and the input / output device based on the iZo request registered in the iZo request queue. IZo request processing system that controls input / output of data performed between the iZo request processing system, the iZo request processing system accepting an iZo request issued by the external device, and the iZo request Processing system power An external device information holding unit that stores the continuous registration failure time for each external device that issued the iZo request, in which iZo requests issued by one external device are not continuously registered in the iZo request queue, and the continuous registration Determining whether to register the accepted iZo request in the iZo request queue with reference to a continuous registration failure time prescribed value storage unit that stores a prescribed value relating to the failure time. The iZo request processing method is provided.

[0011] In the bag request processing system and method according to the third and fourth aspects of the present invention, when an iZo request is received from an external device, the external device continuously fails to register the iZo request; Determine whether to register iZo requests in the iZo request queue based on the specified value for continuous registration failure time. In this case, the iZo request that is issued from an external device with a long continuous registration failure time is given priority to be registered in the iZo request queue, so that the iZo request queue is issued for each external device after the iZo request is issued. Until registered By minimizing the maximum time, the buffer overflow and underflow in the upper system and application can be prevented.

[0012] In the fifth aspect, the present invention registers an IZO request that has also received external device power in an IZO request queue, and establishes a connection between the external device and the input / output device based on the ιΖο request registered in the ιΖο request queue. ΙΖο request processing system that controls the input and output of data performed between the ι ο request accepting unit issued by the external device, and when the ιΖο request accepting unit accepts an iZo request, IZo requests issued by the device are not continuously registered in the iZo request queue.The external device information holding unit stores the number of consecutive registration failures for each external device from which the iZo request is issued. A preferential external device determination unit that determines whether to register the received iZo request in the iZo request queue with reference to the stored continuous registration failure frequency prescribed value storage unit is provided. IZo request processing system is provided.

[0013] In the sixth aspect, the present invention registers the ΙΖΟ request that has also received the external device power in the ΙΖΟ request queue, and determines whether the external device and the input / output device are based on the iZo request registered in the iZo request queue. IZo request processing system that controls input / output of data performed between the iZo request processing system, the iZo request processing system accepting an iZo request issued by the external device, and the iZo request Processing system power An external device information holding unit that stores the number of consecutive registration failures that are not continuously registered in the iZo request queue issued by one external device for each external device that issued the iZo request, and the continuous registration Determining whether to register the accepted iZo request in the iZo request queue with reference to a continuous registration failure frequency prescribed value storage unit that stores a prescribed value relating to the number of failures. An iZo request processing method is provided.

[0014] In the ΙΖΟ request processing system and method according to the fifth and sixth aspects of the present invention, when an iZo request is received from an external device, the priority external process determination unit continuously fails to register the iZo request. And the specified value for the number of consecutive registration failures

Determine whether to register iZo requests in the iZo request queue. Priority external device judgment unit Forces iZo requests issued from external devices with a large number of consecutive failed failures to be registered in the ι / ο request queue prior to issuing iZo requests for each external device. It is possible to minimize the maximum time from registration to the iZo request queue to prevent buffer overflow or underflow in the upper system or application.

In the では request processing system and method of the present invention, the iZo request to be preferentially registered in the iZo request queue is determined based on the registration delay time of the ΙΖΟ request, the number of consecutive registration failures, or the number of consecutive registration failures. . In this way, for example, when accessing a low-speed input / output device such as reading or writing, the maximum delay time of the iZo request of each external device is minimized, so Buffer overflow and underflow in the application can be prevented. As a result, for example, when writing data, the amount of buffer for storing write data and the like can be reduced, so that the amount of buffer provided in the external device can be reduced. In addition, when reading data, it is possible to reduce the amount of prefetching when reproducing video data and the like, and the amount of buffer provided in the external device can be reduced.

Brief Description of Drawings

FIG. 1 is a block diagram showing a configuration of a bag request processing system according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a first operation procedure of the lZO request processing system 500.

FIG. 3 is a flowchart showing a second operation procedure of the lZO request processing system 500.

FIG. 4 is a table showing a specific example of information held by the process information holding unit 510.

FIG. 5 is a table showing specific examples of specified values held by specified value holding unit 550.

FIG. 6 is a table showing a specific example of information held by the lZO request queue information holding unit 530.

FIG. 7 is a table showing specific examples of lZO requests.

FIG. 8 is a flowchart showing a third operation procedure of the lZO request processing system 500.

FIG. 9 is a flowchart showing a fourth operation procedure of the lZO request processing system 500.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the configuration of a bag request processing system according to an embodiment of the present invention. ΙΖΟRequest processing system 500 includes ΙΖΟrequest receiving unit 501, process information holding unit 510, priority process determining unit 520, ΙΖΟrequest queue information holding unit 530, ΙΖΟrequest queue 540, and specified value holding unit 550. Is provided. The IZO request processing system 500 has an external device (process) 600 that is an input / output device 7

00, for example, an IZO request issued to a data storage device such as a DVD (Digital Versatile Disk) or a hard disk (HDD) is accepted, registered in the request queue 540, and stored in the request queue 540. Requests are sequentially passed to I / O device 700. If the IZO request processing system 500 fails to register the IZO request in the IZO request queue 540, the IZO request processing system 500 returns a message to that effect to the process that issued the request. Alternatively, the registration operation is repeated until registration to the ιΖο request queue 540 is successful.

The ΙΖΟ request receiving unit 501 receives an I ΖΟ request indicating a write or read request from the process 600. The priority process determination unit 520 determines a priority process using an algorithm, and stores an IZO request from the process in the IZO request queue 540. The process information holding unit 510 holds predetermined process information for each process 600. More specifically, for each process 600, the number of IZO request failures indicating the number of IZO request failures 51

1 ΐΖ Indicates the elapsed time from when the θ request is received until it is registered in the request queue 540 ΙΖΟ Request delay time 512, ZO IZO registration success time indicating the time when the request was successfully registered in the request queue 540 513, indicating that the IZO request has been successfully registered in the IZO request queue 540, ΙΖΟregistration success flag 514, ΙΖΟindicating the end time of processing to lower the request registration priority 登録 decrease end time 515, ΙΖΟrequesting IZO request time 516 indicating the time, and ΙΖΟrequest continuous failure time 517 indicating the continuous failure time of IZO request registration in the IZO request queue 540 are held.

The cocoon request queue 540 is configured as a queue that holds one or a plurality of cocoon requests connected in a list structure. ΙΖΟRequest queue information holding unit 530 holds information regarding the usage status of ΙΖΟrequest queue 540. More specifically, the usage rate 531 indicating the ratio of the area in which requests are registered in the request queue 540 to the request accommodating area, and the usage number 532 indicating the number of requests registered in the I / O request queue 540 , And the remaining number 533 that can be registered, and the remaining number 533 indicating the number of requests are stored. The specified value holding unit 550 holds a specified value used when the priority process determining unit 520 determines a priority process. More specifically, \ / Ο The request delay time of Ο request, or ΙΖΟ Request Tw specified value 551 used for comparison of continuous failure time of request, and wc specified value 552 used for comparison of the number of consecutive failures of IZO request, , I / O Holds the IZO request queue rate specified value 553 used for request usage rate comparison and the Td specified value 554 used when comparing the intervals in which ΙΖΟ requests from the same process are not received.

The priority process determination unit 520 includes a delay time detection unit 521, a failure count detection unit 522, an attenuation determination unit 523, and a continuous failure time detection unit 524. The delay time detection unit 521 compares the delay time from when an I / O request is received until it is registered in the IZO request queue 540. The failure count detection unit 522 compares the number of failed registrations of the request to the request queue 540. The attenuation determination unit 523 determines the time to decrease the registration priority of the process defect request. The continuous failure time detection unit 524 compares the times when the registration of the request to the request queue 540 fails continuously.

In the following, processing from when an IZO request processing system 500 power ZO request is received until it is registered in the IZO request queue 540 will be described. FIG. 2 shows an operation procedure of the request processing system 500 when a request with a long delay time is preferentially registered in the request queue 540. In this example, the IZO request processing system 500 repeats the registration process until a request is registered in the IZO request queue 540, and the process 600 of the IZO request issuer until the request is registered in the request queue 540. Block processing.

First, the priority process determination unit 520 determines whether or not the IZO request reception unit 501 has received a new IZO request from the process 600 (step Sll). When a new IZO request is received, the IZO request delay time (Tw) 512 for the process 600 is set to 0, and the IZO request time (Tr) 516 is set to the current time (step S12). As the time unit, for example, nanoseconds or the number of clocks for central processing can be used. Thereafter, it is determined whether or not an unregistered IZO request remains in the IZO request queue 540 (step S13). When all the received requests are registered in the request queue 540, the process returns to step S11.

[0023] Among the received IZO requests, if there are still IZO requests that are not registered in the IZO request queue 540, the delay time detection unit 521 causes the process corresponding to each input request to be The request delay time (Tw) 512 is compared, and the one having the maximum delay time is selected (step S14). After that, refer to the IZO request queue information holding unit 530. It is then determined whether or not the I / O request queue 540 is full, that is, whether or not the remaining number 533 is 0 (step S15). If IZO request queue 540 is full, all received I requests corresponding to request issuing process 600 ΙΖΟ request delay time (Tw) 512, IZO request time (Tr) 516 subtracted from current time Set to (Step SI 6) and return to Step SI 1.

[0024] When there is an IZO request storage area that can be registered in IZO request queue 540, the IZO request selected in step S14 is registered in IZO request queue 540 (step S17). The priority process determination unit 520 sets the IZO request delay time (Tw) 512 of the process corresponding to the strong I / O request registered in step S17 to the time obtained by subtracting the IZO request time (Tr) 516 from the current time. Set and return to step S11 to continue the IZO request registration process. By doing this, it is possible to preferentially register the IZO request of 600 processes with a long time during which registration of the request has failed more preferentially in the IZO request queue 540, and the process of process 600 is blocked. Time can be shortened.

FIG. 3 shows an operation procedure of the request processing system 500 when a request of a process that has failed to register a request is preferentially registered in the I request queue 540. In the following example, if registration to the IZO request queue 540 fails, the IZO request processing system 500 returns that fact to the process 600 of the request issuer. Each process 600 receives a notification from the request processing system 500 that the request registration has failed.

For example, wait for a predetermined time and resend the ιΖο request.

[0026] The priority process determination unit 520 determines whether or not the 受信 request receiving unit 501 has received the ΙΖΟ request from the process (step S21). When the プロセス request is not received, the process returns to step S21.まで Wait until a request is received. When the priority process determination unit 520 determines that the ΙΖΟ request reception unit 501 has received an IZO request, whether or not the IZO request continuous failure time (Tw) 517 of the process 600 corresponding to the received IZO request is 0 is determined. Is determined (step S22). When the IZO request continuous failure time (Tw) 517 is 0, it indicates that the I / O request has been received for the first time, and the priority process determination unit 520 indicates that the IZO request time (Tr ) 516 is set to the current time (step S23).

[0027] The priority process determination unit 520 includes an IZO request queue information holding unit 530 and a specified value holding unit. Referring to 550, it is determined whether or not the usage rate 531 is greater than or equal to the predetermined rate specified in the IZO request queue rate specified value 553 as a threshold value (step S24). If it is determined in step S24 that the usage rate 531 is smaller than the predetermined rate A, the received IZO request is registered in the request queue 54 0 (step S27), and the request continuous failure time (Tw) 517 is set to 0. (Step S28), return to Step S21.

[0028] When the priority process determination unit 520 determines in step S24 that the usage rate 531 is equal to or greater than the predetermined rate A, the continuous failure time detection unit 524 causes the continuous IZO request of the process 600 corresponding to the received IZO request to be received. It is determined whether the failure time (Tw) 517 is equal to or longer than the time “TwA” defined by the Tw defined value 551 (step S25). Alternatively, when the IZO request continuous failure time (Tw) 517 of each process 600 is sorted in descending order, the process 600 corresponding to the received IZO request ΙΖΟ Request continuous failure time (Tw) 517 ranking power Tw specified value 551 Judge whether or not it is higher than the rank “Tw rank A” specified in.

If the priority process determination unit 520 determines in step S25 that “TwA” or higher or “Tw rank A” or higher, the process proceeds to step S27 and registers the IZO request in the IZO request queue 540. . On the other hand, if it is determined that it is smaller than “TwA” or lower than “Tw rank A”, IZO request continuous failure time (Tw) 517 is subtracted from IZO request time (Tr) 516 from the current time. (Step S26), the fact that registration to the I / O request queue 540 has failed is returned to the process 600 that issued the I / O request, and the process returns to step S21.

[0030] Here, a case where there are three processes Px, Py, and Pz that issue an IZO request will be described as an example. The process information holding unit 510 stores information shown in FIG. 4 for each process. Further, it is assumed that the specified value holding unit 550 stores the specified value shown in FIG. 5, and the IZO request queue information holding unit 530 stores the information shown in FIG. In this situation, when the IZO request receiving unit 501 receives a ΙΖΟwrite request as shown in FIG. 7 from the process Ρχ in step S21, the ΙΖΟrequest continuous failure time (Tw) 5 17 of the process Ρχ is not 0. The process proceeds from step S22 to step S23.

[0031] In step S24, the IZO request queue 540 usage rate 531 “80%” force specified value holding unit 5 50 is the predetermined rate of the IZO request queue rate specified value 553 以上 “50%” or more, so step S2 5 Proceed to In step S25, IZO request continuous failure time of process Ρχ 517 (Tw: 300η Comparing s) with the time TwA “250 ns” specified by the Tw specification value 551, the IZO request continuous failure time (Tw) 517 of the process Px is larger. Therefore, the process proceeds to step S27 and is registered in the IZO request power IZO request queue 540 of the process Px. Thereafter, the IZO request continuous failure time (Tw) 517 of the process Px is reset to 0 in step S28.

In the above situation, when the IZO request receiving unit 501 receives an IZO request from the process Py in step S21, the process proceeds from step S22 to steps S23, S24, and S25 as described above. Process Py's IZO request continuous failure time 517 (Tw: 200 ns) is smaller than the time TwA “250 ns” defined by Tw standard value 551. If the rank of the process Py's I / O request continuous failure time 517, which has a long delay time, is compared with the "Tw rank A" and "2nd" defined in the Tw regulation value 551, the process Py's IZO request consecutive failure time (Tw) 517 rank “2nd” is higher than “Tw rank A” “2nd”. Therefore, the process proceeds from step S25 to step S27 and is registered in the IZO request power IZO request queue 540 of the process Py.

[0033] In the above situation, when the IZO request receiving unit 501 receives an IZO request from the process Pz in step S21, in step S25, when the request consecutive failure times are compared, the IZO request continuous failure time of the process Pz is 517. (Tw: 100ns) is smaller than the time TwA “250ns” specified by the Tw specification value 551. Also, the ranking “3rd” from the longest I / O request failure time 517 of process Pz is lower than the Tw ranking A “2nd”. For this reason, the process proceeds from step S25 to step S26, and the IZO request of the process Pz is not registered in the I / O request queue 540.

[0034] When adopting a method of registering ΙΖΟ requests in the queue according to the activation priority as in the conventional ΙΖΟ request processing system, since the time during which iZo request registration has failed is not considered, If the start priority of process Pz is the highest, the IZO request issued by process Pz is registered in the queue first, and the registration of the ΙΖΟ request is compared to the time when the process Pz ΙΖΟ request registration failed. IZO requests issued by processes Px and Py that have failed for a long time lose their registration opportunity. In accordance with the procedure shown in Fig. 3, by adopting a configuration that registers ΙΖΟrequests in ΙΖΟrequest queue 540, ΙΖΟrequests from process 600 that have failed to register ΙΖΟrequests are given priority. queue The maximum delay time from when each process 600 generates an IZO request until it is registered in the IZO request queue 540 can be minimized.

[0035] FIG. 8 shows an operation procedure of the IZO request processing system 500 when preferentially registering IZO requests from the process 600, which has frequently failed to register IZO requests, in the IZO request queue 540. ing. The priority process determination unit 520 determines whether or not the power request receiving unit 501 has received a power request newly from the process 600 (step S31). If a new IZO request has not been received, the process returns to step S21 and waits until a new input request is received. When the priority request determination unit 520 determines that the input request receiving unit 501 has received a new input request, the priority process determination unit 520 determines whether or not the process 600 corresponding to the received input request is the first process to issue the input request. Step S32). If the process 600 makes an I / O request for the first time, the IZO request failure frequency (wc) 511 of that process is set to 0 (step S33).

[0036] The priority process determining unit 520 refers to the request queue information holding unit 530 and the specified value holding unit 550, and the usage rate 531 is a predetermined rate specified in the request queue rate specified value 553 as a threshold value. It is determined whether or not this is the case (step S34). For example, when the specified value holding unit 550 holds the information shown in FIG. 5, a value (60%) corresponding to the predetermined rate B is acquired from the specified value holding unit 550, and the usage rate 531 Judge whether the force is 60% or more. If it is determined in step S24 that the usage rate 531 is smaller than the predetermined rate B, the received IZO request is registered in the IZO request queue 540 (step S37), and the IZO request failure frequency (wc) 511 is set to 0. (Step S38), the process returns to step S31.

[0037] When the priority process determination unit 520 determines in step S34 that the usage rate 531 is greater than or equal to the predetermined rate Β, the failure count detection unit 522 causes the failure count detection unit 522 to execute the 600 request failure count ( wc) It is determined whether 511 is equal to or greater than the number of failures “wcA” specified by the wc specified value 552 (step S35). Alternatively, when the number of I / O request failures (wc) 511 of each process 600 is sorted in descending order, the rank of the request failure number (wc) 511 of the process corresponding to the received IZO request is the wc specified value 552. It is determined whether or not the rank is higher than the rank “wc rank c” defined in. For example, when the specified value holding unit 550 holds the information shown in FIG. 5, the priority process determining unit 520 determines that the number of failed requests (wc) 511 is lost. It is determined whether or not the number of losses is “wcA” (60 times) or more, or whether or not the number of IZO request failures (wc) is 511's order power S ”wc rank A” (4th) or more.

If it is determined in step S35 that it is “wcA” or higher, or “wc rank A” or higher, the process proceeds to step S37 and an IZO request is registered in the IZO request queue 540. On the other hand, if it is determined that it is smaller than “wcA” or lower than “wc rank A”, 1 is added to the IZO request failure count (wc) 511 (step S36), and the process that issued the IZO request is added. Return that IZO request queue registration failed to 540 and return to step S31. By registering 1 / Ο requests to ΙΖΟ request queue 540 in this way, ΙΖΟ IZO requests from processes that have failed to register ΙΖΟ requests are preferentially registered to IZO request queue 540. As a result, the maximum required delay time for each process 600 can be minimized.

[0039] FIG. 9 shows an operation procedure of the IZO request processing system 500 0 when a process 600 that does not issue an IZO request for a long time attenuates the registration of the request to the IZO request queue 540 for a while. ing. The priority process determination unit 520 determines whether the heel request reception unit 501 has received an IZO request from the process 600 (step S401). When the IZO request is not received, the process returns to step S401 and waits until the ΙΖΟ request is received.

[0040] When the priority request determination unit 520 determines that the input request reception unit 501 has received the input request, the priority process determination unit 520 determines whether or not the process 600 corresponding to the received input request is the first process to execute the input request. (Step S402). If this is the first process to make an IZO request, set the current time for ΙΖΟregistration success time 513 (Ts) and IZO decay end time 515 (Te), and I / O registration success flag (sFlg) 514 Is set to “1” indicating success (step S410), and the process proceeds to step S406.

[0041] When the priority process determination unit 520 determines in step S402 that the process is not the first I / O request process, the I / O registration success flag (sFlg) 514 indicates success "1". (Step S403). If the IZO registration success flag (sFlg) 514 does not indicate success “1”, the process proceeds to step S406. When the IZO registration success flag (sFlg) 514 indicates “1”, the priority process determination unit 520 subtracts the time Ts when the previous I / O request was successfully registered from the current time, Calculate the time Td when the / O request is strong (Step S404).

The priority process determination unit 520 refers to the Td specified value 554, and determines whether or not the time Td calculated in step S404 is larger than the specified value “TdA” (step S405). For example, when the specified value holding unit 550 holds the information shown in FIG. 5, whether the calculated Td force is greater than 500 ns by obtaining the specified value “TdA” (500 ns) from the specified value holding unit 550. Judge. Time when IZO request is strong Td force When it is larger than the specified value “TdA”, the time obtained by adding the decay time specified by the Td specified value 554 to the current time is defined as the IZO decay end time 515 (Te). Set (Step S411). For example, when the specified value holding unit 550 holds the information shown in FIG. 5, the time when the decay time (1,0,000,000 ns) specified by the specified value holding unit 550 is added to the current time. Set the IZO decay end time to 515 (Te). If the time Td when there was no I / O request is less than or equal to the specified value "TdA", proceed directly to step S406.

[0043] The priority process determination unit 520 refers to the IZO request queue information holding unit 530 and the specified value holding unit 550, and the usage rate 531 is a predetermined rate C specified in the request queue rate specified value 553 as a threshold value. It is determined whether or not the above is true (step S406). For example, when the specified value holding unit 550 holds the information shown in FIG. 5, a value (70%) corresponding to the predetermined rate C is acquired from the specified value holding unit 550, and the usage rate 531 Judge whether it is (70%) or more. If it is determined in step S406 that the usage rate 531 is smaller than the predetermined rate C, the received IZO request is registered in the ΙΖΟ request queue 540 (step S412), ΙΖΟ registration success time 513 (Ts), and IZO decay The end time 515 (Te) is set to the current time, the \ / O registration success flag (sFlg) 514 is set to success “1” (step S413), and the process returns to step S401.

[0044] When the priority process determination unit 520 determines in step S406 that the usage rate 531 is equal to or greater than the predetermined rate C, the attenuation determination unit 523 compares the current time with the IZO attenuation end time 515 (Te). Then, it is determined whether or not the current time is before the IZO decay end time 515 (Te) (step S407). If it is determined that the current time force ZO decay end time 515 (Te) is not earlier than the current time force ZO decay end time 515 (Te), the process proceeds to step S412 and the IZO request is routed to the IZO request queue. Register with 540. If the priority process determination unit 520 determines in step S407 that the current time force / 0 decay end time 515 (Te) is earlier than the IZO requirement measured in the same procedure as shown in FIG. It is determined whether or not the requested continuous failure time (Tw) 517 exceeds the specified value specified by the specified value holding unit 550 (step S408). Alternatively, whether or not the number of IZO request failures (wc) 511 counted in the same procedure as shown in FIG. 8 exceeds the specified value specified by the specified value holding unit 550 (or is it more than the specified value) ).

In step S408, for example, referring to the specified value holding unit 550 (FIG. 5), the I / O request continuous failure time (Tw) 517 is equal to or longer than the delay time “TwB” (300 ns), or It is determined whether or not the I / O request continuous failure time (Tw) 517 rank is "Tw rank B" (4th place) or more. Or, IZO request failure frequency (wc) 511 is more than the failure frequency “wcB” (70 times) or IZO request failure frequency (wc) 511 ranking power “wc ranking B” (5th) or more Judge whether there is any power.

If priority process determination section 520 determines that the specified value is exceeded in step S408, it proceeds to step S412 and registers the IZO request in IZO request queue 540. If it is determined in step S408 that the specified value is not exceeded, the registration success flag (sFlg) 514 is set to “0” (failure) (step S409), and the process returns to step S401. By registering an IZO request to the I ΖΟ request queue 540 in such a procedure, the process 600 that does not send an IZO request for a long time is connected to the I / O request queue 540 until the IZO decay end time 515. The priority can be lowered and IZO requests from other processes 600 can be preferentially registered in the IZO request queue 540.

In this embodiment, when the usage rate of the ΙΖΟrequest queue 540 is high, that is, when the remaining number that can be registered is small, the priority process determination unit 520 performs ΙΖΟrequest delay time 512 or ΙΖΟrequest continuous failure time. 517 registers the request from the long process 600 with priority to the request queue 540. Alternatively, a process with 600 IZO request failures 511 with a large number of 511 requests is registered in the request queue 540 with priority. In this way, it becomes possible to significantly reduce the delay time of access such as reading or writing for a low-speed device, for example. Save write data in applications and devices The amount of notching can be reduced. In reading, when reproducing video data or the like, the amount of prefetching can be reduced, and the buffer amount can be reduced.

It should be noted that the registration processing to the IZO request queue 540 described in the above embodiment can be used in combination. For example, the priority process determination unit 520 first registers in the request queue 540 based on the request delay time 512 according to the procedure shown in FIG. 3, and then fails in the request request according to the procedure shown in FIG. A configuration may be adopted in which registration in the request queue 540 is performed based on the number of times 511. Further, the ΙΖΟ request may be registered with a procedure shown in FIG. 3 for a specific storage device, and the \ / Ο request may be registered with the procedure shown in FIG. 4 for other storage devices. In step S25 and the like, the judgment may be made based on whether or not the required delay time 512 exceeds a prescribed value for determining whether or not the required delay time 512 is greater than or equal to the prescribed value. In step S24, etc., it was determined whether or not the usage rate 531 is greater than or equal to the specified value, but instead of the usage rate 531, the number of used 532 or the remaining number 533 was used, and whether or not the number of used 532 was smaller than the specified value. Alternatively, the determination may be made based on whether or not the remaining number 533 is not less than a specified value.

[0050] As described above, the present invention can employ the following modes. In the bag request processing system according to the third aspect of the present invention, the continuous registration failure time prescribed value holding unit holds a threshold value of the continuous registration failure time, and the priority external device determination unit accepts the acceptance.構成 If the continuous registration failure time of the external device that issued the request is equal to or greater than the threshold value, the received iZo request can be registered in the iZo request queue.

. In the fourth aspect of the present invention, the continuous registration failure time prescribed value holding unit stores a threshold value of the continuous registration failure time and determines whether or not to register. The step can adopt a configuration in which the received iZo request is registered in the iZo request queue when the continuous registration failure time of the external device that issued the accepted iZo request is equal to or greater than the threshold value. When using the threshold value for continuous registration failure time as the default value, iZo requests with an external device whose continuous registration failure time is equal to or greater than the threshold value are preferentially registered in the iZo request queue. This makes it possible to minimize the maximum amount of time it takes to register in the iZo required power Ζο request queue.

[0051] In the bag request processing system according to the third aspect of the present invention, the continuous registration failure time rule The value holding unit holds a threshold value of the order of consecutive registration failure times, and the priority external device determining unit arranges the received iZo when the consecutive registration failure times of the external devices are arranged in descending order. If the rank of the external device that issued the request is equal to or higher than the threshold of the consecutive registration failure count, the received iZo request is registered in the request queue described above. Configuration can be adopted. Further, in the iZo request processing method according to the fourth aspect of the present invention, the continuous registration failure time prescribed value holding unit holds a threshold value of the rank of the continuous registration failure time and determines whether or not to register. The order in which the consecutive registration failure times of the external devices are arranged in descending order is that the rank of the external device that issued the accepted iZo request is the same as the value of the threshold of the number of consecutive registration failures. Or, if the rank is higher than this, it is possible to adopt a configuration in which the accepted iZo request is registered in the iZo request queue. When using the threshold value for the order of consecutive registration failure times in descending order as the default value, iZo requests that are issued from external devices whose consecutive registration failure time order is equal to or higher than the threshold. By prioritizing and registering in the iZo request queue, it is possible to minimize the maximum time required for registration in the iZo request power Ζο request queue.

In the flaw request processing system according to the fifth aspect of the present invention, the continuous registration failure frequency prescribed value holding unit holds a threshold value of the continuous registration failure frequency, and the priority external device determination unit receives the received iZo If the number of consecutive registration failures of the external device that issued the request is equal to or more than the threshold of the number of consecutive registration failures described above, the received iZo request is

It is possible to adopt a configuration that registers in the request queue. In the bag request processing method according to the sixth aspect of the present invention, the continuous registration failure frequency prescribed value holding unit holds a threshold value of the continuous registration failure frequency and determines whether or not to register. The accepted I

Ζο When the number of consecutive registration failures of the external device that issued the request is equal to or greater than the threshold value of the number of consecutive registration failures, the received iZo request can be registered in the iZo request queue. When using the threshold value for the number of consecutive registration failures as the default value, iZo requests that are issued from an external device whose consecutive registration failure count is equal to or greater than the threshold value are registered in the iZo request queue with priority This makes it possible to minimize the maximum amount of time required to be registered in the iZo required power Ζο request queue. [0053] In the IZO request processing system according to the fifth aspect of the present invention, the continuous registration failure frequency prescribed value holding unit holds a threshold value of the rank of the continuous registration failure frequency, and the priority external device determination unit When the consecutive registration failure counts of the external device are arranged in descending order, the rank of the external device that issued the received ΙΖΟ request is the same rank as the value of the consecutive registration failure count rank, or If the rank is higher than this, it is possible to adopt a configuration in which the accepted iZo request is registered in the request queue. Also, in the sixth aspect of the request processing method of the present invention, the continuous registration failure frequency prescribed value holding unit holds a threshold value of the rank of the continuous registration failure frequency, and determines whether or not to register. The order of the consecutive registration failure counts of the external devices is arranged in descending order, and the rank of the external device that has issued the accepted iZo request is the same rank as the threshold value of the consecutive registration failure count Alternatively, a configuration in which the received iZo request is registered in the iZo request queue can be adopted when the rank is higher than this. When using the threshold of the order when the number of consecutive registration failures is arranged in descending order as the default value, the iZo request is issued from an external device whose order of consecutive registration failures is greater than or equal to the threshold. By prioritizing and registering in the iZo request queue, it is possible to minimize the maximum time required for registration in the iZo request power Ζο request queue.

When the priority external device determination unit determines that the received iZo request is not registered in the iZo request queue, the iZo request processing system according to the third and fifth aspects of the present invention A configuration can be adopted in which the fact that registration to the iZo request queue has failed is returned to the external device that issued this. In the ΙΖΟrequest processing method of the fourth and sixth aspects of the present invention, when it is determined that the received iZo request is not registered in the IΖO request queue in the step of determining whether or not to register, the iZo Request processing system capability ΙΖ ο A configuration can be adopted that further includes a step of returning to the external device that issued the request that the registration to the iZo request queue has failed. In this case, the external device that has received the notification of the failure may wait for a predetermined time, for example, and retransmit the iZo request.

In the bag request processing system according to the third and fifth aspects of the present invention, the priority determination unit includes an iZo request queue information holding unit that stores a usage rate of the iZo request queue, and a specified value related to the usage rate The iZo request queue specified value storage unit When the rate is smaller than the specified value, it is possible to adopt a configuration in which it is determined that the accepted iZo request is registered in the iZo request queue. According to the second and third aspects of the soot request processing method of the present invention, the iZo request processing system stores an iZo request queue information holding unit that stores the usage rate of the iZo request queue, and a prescribed value related to the usage rate. A step of comparing the usage rate with a specified value related to the usage rate with reference to an iZo request queue specified value holding unit, and if the usage rate is smaller than a specified value related to the usage rate, the I

要求 ο request processing system power A configuration can be adopted that further includes the step of registering the received iZo request in the iZo request queue. If the usage rate is low, there is room in the iZo request queue. In such a state, the iZo request can be registered in the iZo request queue without deciding whether to register the iZo request based on the specified value.

The request processing system according to the third and fifth aspects of the present invention holds a time interval when a request is received from the external device and a time interval specified value holding unit that holds a threshold value of the time interval. If the received time interval is compared with a threshold value and it is determined that the received time interval exceeds the threshold value of the time interval, it indicates the end time of the time to lower the registration priority of the iZo request issued by the external device It is possible to employ a configuration further including an attenuation time setting unit that stores the attenuation end time in association with the external device. In this case, the priority external device determination unit compares the current time with the decay end time, and determines that the current time is after the decay end time, the received iZo request is sent to the iZo request queue. It is possible to adopt a configuration that is determined by registering in According to the fourth and sixth aspects of the present invention, the wrinkle request processing method holds the time interval when the iZo request is received from the external device and the time interval specified value holding unit that holds the threshold value of the time interval. Comparing the threshold with

If it is determined that the received time interval exceeds the time interval threshold, the request processing system sets the end time of the time to lower the registration priority of the iZo request issued by the external device. It is possible to employ a configuration further including a step of storing the attenuation end time shown in association with the external device. In this case, in this case, when the iZo request processing system determines that the current time is after the decay end time in the comparing step of the current time and the decay end time, the iZo request processing system A configuration may be adopted that further includes a step of registering the accepted iZo request in the iZo request queue. In this case, by setting an attenuation end time for an external device with a long iZo request issuance interval (reception interval), priority is given to registration of iZo requests from that external device until that time is reached. IZo requests from other external devices can be preferentially registered in the iZo request queue. The decay end time can be calculated, for example, as a time obtained by adding a predetermined time to the time when the last iZo request is registered in the iZo request queue.

As described above, the present invention has been described based on its preferred embodiments. However, the cocoon processing system of the present invention is not limited to the above-described embodiment examples, and the configuration force of the above-described embodiments is variously modified and changed. What has been done is also included in the scope of the present invention.

Claims

The scope of the claims

[1] Register an iZo request received from an external device in the iZo request queue and control data input / output between the external device and the input / output device based on the ιΖο request registered in the iZo request queue iZo request processing system,

Receives a request issued by the external device (600) A request accepting unit (501) and an external device information holding unit (510) for storing a delay time from receiving the iZo request to registering in the iZo request queue The priority external device determination unit (520) that registers the trap request having the longest delay time among the trap requests received by the trap request receiving unit (501) in the trap request queue (540). A request processing system characterized by comprising:

[2] Register the ΙΖΟ request received from the external device in the iZo request queue, and control data input / output between the external device and the input / output device based on the iZo request registered in the iZo request queue iZo request processing system,

ΙΖΟRequests received by the external device (600) ΙΖΟRequest accepting unit (501) and ΙΖΟRequest accepting unit (501) When receiving a ZO request, 外部 requests issued by one external device (600) are consecutive The external device information holding unit (510) that stores the continuous registration failure time for each external device (600) that issued the request without registering in the request queue (540) Referring to the continuous registration failure time regulation value storage unit (517) that stores the value, the priority external device determination unit that determines whether or not to register the received ΙΖΟ request in the ΙΖΟ request queue (540). IZo request processing system characterized by having 520).

[3] The continuous registration failure time prescribed value holding unit (517) holds a threshold value of the continuous registration failure time, and the priority external device determination unit (520) The ΙΖΟ request processing system according to claim 2, wherein when the continuous registration failure time of the external device (600) is equal to or greater than the threshold value, the accepted ΙΖΟ request is registered in the ΙΖΟ request queue (540).

[4] The continuous registration failure time prescribed value holding unit (517) holds a threshold value of the order of consecutive registration failure times, and the priority external device determination unit (520) is configured to store the external device (600). When the consecutive registration failure times are arranged in descending order, the rank of the external device (600) that issued the accepted IZO request is the same rank as the threshold of the number of consecutive registration failures! /, Or 3. The wrinkle request processing system according to claim 2, wherein if it is higher in rank, the received wrinkle request is registered in the wrinkle request queue (540).

[5] Registers a request received from an external device in the request queue, and controls data input / output between the external device and the input / output device based on the request registered in the request queue. ιΖο request processing system,

ΙΖΟRequests received by the external device (600) ΙΖΟRequest accepting unit (501) and ΙΖΟRequest accepting unit (501) When receiving a ZO request, 外部 requests issued by one external device (600) are consecutive The external device information holding unit (510) that stores the number of consecutive registration failures that are not registered in the request queue (540) for each external device (600) that issued the request, and the rules for the number of consecutive registration failures A prioritized external device determination unit that determines whether or not the received ΙΖΟ request is registered in the ΙΖΟ request queue (540) with reference to the continuous registration failure frequency prescribed value storage unit (552) that stores a value; Ο Ο Request processing system characterized by that.

[6] The continuous registration failure frequency prescribed value holding unit (552) holds the threshold value of the continuous registration failure frequency! / ヽ value, and the priority external device determination unit (520) issues the received ΙΖΟ request. If the number of consecutive registration failures of the original external device (600) is equal to or greater than the threshold of the number of consecutive registration failures, the received request is registered in the request queue (540). ΙΖΟRequest processing system described in 5.

[7] The continuous registration failure frequency prescribed value holding unit (552) holds a threshold of the order of the continuous registration failure frequency, and the priority external device determining unit (520) is configured to store the external device (600). When the consecutive registration failure counts are arranged in descending order, the rank of the external device (600) that issued the received ΙΖΟ request is the same rank as the threshold of the consecutive registration failure count rank! /, Or If the rank is higher than this, the received trap request is transferred to the trap request queue (54 The IZO request processing system according to claim 5, which is registered in (0).

[8] When the priority external device determination unit (520) determines that the received trap request is not registered in the trap request queue (540), the trap request processing system (500) issues the trap request issuer. The trap request processing system according to any one of claims 2 to 7, wherein a failure to register in the trap request queue (540) is returned to the external device (600).

[9] The priority external device determination unit (552) stores a usage rate of the request queue (540), a request queue information holding unit (530), and a specified value related to the usage rate I request. The queue specified value holding unit (553) is referred to, and if the usage rate is smaller than the specified value, it is determined that the received trap request is registered in the trap request queue (540). 7. The request processing system according to any one of 7 above.

[10] The time interval at which the ΙΖΟ request is received from the external device (600) is compared with the threshold value held by the time interval specified value holding unit (554) that holds the threshold value of the time interval. When it is determined that the received time interval exceeds the threshold value of the time interval, the attenuation end time indicating the end time of the time to lower the registration priority of the request issued by the external device (600) is set. The saddle request processing system according to any one of claims 2 to 7, further comprising an attenuation time setting unit (515) for storing the external device (600) in association with the external device (600).

[11] The prioritized external device determination unit (520) compares the current time with the attenuation end time, and when determining that the current time is after the attenuation end time, the priority external device determination unit (520) 11. The coffee request processing system according to claim 10, which is determined to be registered in the coffee request queue (540).

[12] Registers a request received from an external device in the request queue, and controls data input / output between the external device and the input / output device based on the request registered in the request queue. ι する ο request processing system for processing ιΖο request, the step of receiving a ΙΖΟ request issued by the external device (600),

Referring to the external device information holding unit (510) that stores the delay time from when the request is accepted until it is registered in the request queue (540), the delay time is the maximum of the accepted request. And a request queue (step 5409 for registering the request).

[13] Registers an IZO request received from an external device in the IZO request queue, and controls data input / output between the external device and the input / output device based on the ιΖο request registered in the ΙΖΟrequest queue. ι する ο request processing system for processing ιΖο request, the step of receiving a ΙΖΟ request issued by the external device (600),

ΙΖΟ Requests issued by one external device (600) are not continuously registered in the request queue (540)! Continuous device failure information is stored for each external device (600) that issued the request. A holding unit (510) and a continuous registration failure time prescribed value storage unit (551) for storing a prescribed value related to the continuous registration failure time are referred to, and the received ΙΖΟ request is registered in the ΙΖΟ request queue (5409). ΙΖο request processing method characterized by comprising: determining whether or not.

[14] The continuous registration failure time prescribed value holding unit (551) holds a threshold value of the continuous registration failure time, and the step of determining whether or not to register is performed by issuing the accepted ΙΖΟ request The ΙΖΟ request according to claim 13, wherein, when the continuous registration failure time of the original external device (600) is equal to or greater than the threshold, the ΙΖΟ request received is registered in the ΙΖΟ request queue (540). Processing method.

[15] The continuous registration failure time prescribed value holding unit (551) holds a threshold value of the rank of the continuous registration failure time, and the step of determining whether or not to register is performed by the external device (60 0). ) Of consecutive registration failure times in descending order, the rank of the received external device (600) that issued the ΙΖΟ request is the same rank as the threshold of the number of consecutive registration failures! 14. The habit request processing method according to claim 13, wherein if the rank is higher than the rank, the received habit request is registered in the habit request queue (540).

[16] Register ΙΖΟrequest received from external device in ΙΖΟrequest queue, and control data input / output between external device and input / output device based on ιΖοrequest registered in ΙΖΟrequest queue A processing system (a method of processing a request, wherein a step of receiving a request issued by the external device (600);

ΙΖΟ Requests issued by one external device (600) are not continuously registered in the request queue (540)! External device information that stores the number of consecutive registration failures for each external device (600) that issued the request Storage unit (510) and a predetermined value for the number of consecutive registration failures And a step of determining whether or not to register the received IZO request in the ΙΖΟ request queue (540) with reference to the prescribed registration failure frequency prescribed value storage unit (551). Processing method.

[17] The continuous registration failure frequency prescribed value holding unit (551) holds a threshold value of the continuous registration failure frequency, and the step of determining whether or not to register is performed by issuing the accepted ΙΖΟ request 17. The received trap request is registered in the trap request queue (540) when the number of consecutive registration failures of the original external device (600) is equal to or greater than a threshold value of the consecutive registration failure count. ΙΖΟ Request processing method.

[18] The continuous registration failure frequency prescribed value holding unit (551) holds a threshold value of the order of the continuous registration failure frequency, and the step of determining whether or not to register is performed by the external device (60 0). ) Of consecutive registration failure counts in descending order, the rank of the received external device (600) that issued the ΙΖΟ request is the same rank as the threshold of the consecutive registration failure count! / ヽ value, or 17. The wrinkle request processing method according to claim 16, wherein if there is a higher rank, the received wrinkle request is registered in the wrinkle request queue (540).

[19] In the step of determining whether or not to register, if it is determined that the received ΙΖΟ request is not registered in the ΙΖ Ο request queue (540), the external device (600) that issued the ΙΖΟ request is The trap processing method according to any one of claims 13 to 18, further comprising a step of returning that the registration to the trap queue (5409 has failed).

[20] Referring to the ΙΖΟrequest queue information holding unit (530) that stores the usage rate of the ΙΖΟrequest queue and the ΙΖΟrequest queue specified value holding unit (553) that stores the specified value related to the usage rate, Comparing the usage rate with a prescribed value for the usage rate;

The method according to any one of claims 13 to 18, further comprising a step of registering the received coffee request in the coffee request queue (540) when the usage rate is smaller than a specified value related to the usage rate. ΙΖΟ The processing method.

[21] A step of comparing a time interval at which the ΙΖΟ request is received from the external device (600) with a threshold value held by a time interval specified value holding unit (554) that holds a threshold value of the time interval. When the received time interval exceeds the time interval threshold, the external device (600) issues a request for ending the registration priority of the request. The IZO processing method according to any one of claims 13 to 18, further comprising a step of storing the indicated attenuation end time in association with the external device (600).

A step of comparing a current time with the decay end time, and a step of registering the accepted trap request in the trap request queue (540) when the comparison step determines that the current time is after the decay end time. The vaginal request processing method according to claim 21, further comprising: